Centrifugal separator



IJune 16, 1942. H, C, FlTzslMMONs 2,286,355

CENTRIFUGAL SEPARATOR Filed April 16, 1941 5 SheeLs-Sheefl 1 F/g'/ 25 II Vl 1N VEN TOR I? 41M Haro/d C Hbf/771mm A TTORNE Y une l5, 3942s H. c.FITZSIMMONS 2,236,355

CENTRIFUGAL SEPARATOR Filed April 16, 1941 3 Sheets-Shee(l 2 A TTORN E YJune l, 1942. H, C, F|TZ$|MMQN5 2,286,355

CENTRIFUGAL SEPARATOR Filed April 16, 1941 3 Sheets-Sheet 5 INVENTORHaro/d C 'nhnmons I Q1 01W/*4 y ATTORNEY vention,

Patented June 16, 1942 CENTRIFUGAL SEPARATOR Harold C. Fitzsimmons, WestChester, Pa., Vasslgnor to The Sharples Corporation, Philadelphia, Pa.,a corporation of Delaware' AApplication April 16, 1941, Serial No.388,743

I (Cl. 2334-20) 10 Claims.

The present invention pertains to the art of centrifugal separatorsdesigned to effect separation of solids from a liquid, or separation ofsolids from a mixture of liquids.- It pertains lto the type ofcentrifugal in which s olids are intermittently discharged throughvalve-controlled discharge passages in the wall of the centrifugalrotor, such as described in my prior application, Serial No. 318,672,led February 13, 1940, for Centrifugal separator.

i In the machine of that application, the valves are operated by fluidpressure motors to disrial fed to the mainbody of the rotor through theopenings I8 passes upwardly through` the openings I1 intothe spacebetween the stratifycharge the accumulated sludge periodically. In

the design of a centrifugal separator equipped with valves and motors ofthis kind, it is important that an arrangement be provided which isdurable, delicately responsive in operation, and proof against leakagefrom the main body of the rotor through the motor parts. A feature ofthe present invention consists in the fact that it embodies anarrangement which is an improvement over that of my prior application,No. 318,672, in these particulars. A further feature is that theinvention includes a sealing connection in which the sealing is enhancedby the eifect'of centrifugal force in the rotation of the rotor.

In the drawings,

Figure l is la central axial section through the left-hand side of acentrifugal rotor of 'the in- Figure 2 is a detailed sectional view,partly diagramatic, illustrating a cross-section through a motor of oneembodiment of the invention,

` Figure 3 is a perspective view, illustrating the method of mountingthe sealing rings of the motor of Figure 2, and

Figure 4 is a view similar to Figure 2, illustrating an'alternative formof the invention.

The machine of the invention is similar ln most particulars'to that'ofmy prior application ing discs.

'Ihe solids in the liquid fed-to the rotor pass outwardly to theperipheral wall of the rotor and the heavier liquid also passesoutwardly towardv the peripheral wall, and forms a stratum within thedeposited solids. This liquid passes inwardly through the space betweena dividing wall I9 toward the upper end of the rotor, and the upperportion 20 of the rotor, which may be secured to the lmain body of therotor by vthe screw threaded connectionl 2|. uent passes outwardly fromthe rotor across the ringdam 22. The lighter liquid passes inwardlythrough the spaces between the superposed discs I8 into a space 23within the discs, and upwardly through the space 24 between a tubularextension 25 of the dividing wall, and feed tube I5. The liquidcentrifugal eiiluents discharged over ring dam 22 Aand from tube 25 arecollected in separate centrifugal covers, as will be understood by thoseskilled in the art. The inner peripheral wall of the main body of therotor consists of opposed frusto-conical surfaces 26 and 21, and thepoint of maximum diameter of the main body of the rotor is locatedapproximately centrally of this portion of the rotor.

It will be seen that, when a mixture of` liquids and a solid isintroduced into the tube I5, and the centrifugal rotor is rotated athigh speed during the continuous feed of the mixture, the solids aratelydischarged from the rotor as indicated No. 318,672, referred' to above.The rotor is drivy en by a shaft I0 which is driven by any suitable formof motor, not shown. A sleeve I2 surrounds the shaft I0 and is driven bythis shaftl through driving connections of conventional design. The

AI5 and sleeve I2, and through openings I6 in the lower end vof the tubeI5 into-the zone 'of the main body of the rotor occupied by registeringopenings I'I in the stratifying discs I8. Matewill be deposited alongthe surfaces 26 and 21 and flow outwardly along these surfaces to thezone 28, while the liquids are separated and sepabove. The rotor isprovided with a plurality of small passages 29 through which thesesolids are intermittently discharged. These passages may be providedwith bushings 30, radially extending valve guide members 3| (Fig. 2),and valve seats 32, las illustrated. A reciprocating valve 33 isprovided for co-action with each of the valve seats 32, and each ofthese valves 33 is connected with a valve stem 34, which is actuated bymeans to be described hereinafter for intermittent discharge of-deposited solids through vthe valve seats 32 andbushings 30.

Fluid pressure motors 35 operate to move the valves, anv individualmotor being attached to each of the individual valve stems 34, and theAmotors being secured within-the rotor for rotation therewith. Each ofthese motors comprises a housing which consists of an end portion 36This heavier constit- 2 l i 2,286,355 e v to effect sealing contact withthe inner surface and a base portion 31 secured to the portion 36. Thishousing surrounds the moving parts of the motor. The base portion 31 hasan annular extension 38 (see Fig'. 2) which lies adjacent the zone 28 ofaccumulation of solids. end 39 of the valve stem 34 has an inner endportion 4| which is the moving member of the fluid pressure motor and isprovided with a depending annular, flange 42. e 'Ihe housing base 31 isprovided with a lateral extension 55 through which liquid is passed fromthe main body of lthe centrifugal rotor for actuating the fluid pressuremotor.

A bore 56 in extension 55 communicates'with` diagrammatic, in theinterest`of simplicity of' illustration of the principles lof theinvention.) The inner endof conduit 49 is connected to a member 50,which has a bore (see, Fig. 2) communicating with the conduit 49', andalso a channel 52 communicating with the inner end of bore 5|. A bore 53extends outwardly from the .channel 52, and is connected to a second,`and smaller, conduit 54, which extends outwardly from the member 50 to aconnection with a bore 51 in the lateral extension 55 of the housingbase 31.

The bore 51 communicates with the space 58 between the end portion 36 ofthe housing and the outer surface of the movable member 4| of the uidpressure motor. The inner surface of this member 4| communicates withthe sludge space 28 of the rotor, through the hollow interior of themember 59 of the motor, which is a stationary member having avcylindrical outer surface along which` the flange 42 of the movablemember or piston 4| reciprocates. The space 58 is also invcommunication, through an orifice connecting this space with a bore 60in an extension. 6| of the base portion 31 of the motor housing, with anoutlet 62 in the rotor wall, through which motor actuating fluid isdischarged from the machine. It will be noted that,

material discharged through the outlet 62 is discharged at a separatepoint fromthe solids dis-4 charged through the valve 32, and thismaterial is collected separately from the solids.

The most impotrant feature of the invention consists in the provision ofmotor sealing devices designed to function in such a way that thecentrifugal force` due to rotation of the rotor exerts a sealing effecton the sealing members. In the form illustrated in Figures 2 and 3 ofthe drawings, the stationary member or cylinder 59 is provided withflanges 63 and 64, and split metal sealing rings 65 and 66 are confinedbetween these flanges, 'with their outer surfaces contacting the innersurface of the 'flange 42 of the movable member or piston 4|. The splitsin the rings are dsaligned in order to prevent leakage between them,being preferably spaced apart in the assembly of the rings with themotor, as illustrated in Figure 3 of the drawings. The outer (lower,Fig. 2) surface of the outer ring 66 abuts the inner (upper, Fig.'2)surface of the flange 63 of the cylinder 59, and the outer (lower. Fig.2) surface of the ring 65 `abuts the inner (upper, Fig. 2) surface of.the ring 66. The natural resilience of the rings causesthem The innerCal l above, when the machine is first brought up to speed, thevalve 33is forced against the valve seat v32 under the influence of thecentrifugal force' operative upon the valve stem 34 and the piston 4|.`As` the rotor fills with liquid, a part of this liquid enters the spacebetween the extension 38 and the valve stem 34, and the pressure appliedto this liquid by reason of the rotation of the main body of liquidwithin the rotor forces the valve stem 34 to move inwardly and removethe valve 33 from the valve seat 32. As the body of liquid in the rotorbecomes deeper, liquid entering between the parts 38 and 34, passingthrough bore 56, enters conduit 49 and passes inwardly through thisconduit (see Fig. 2). The innerend of the-bore 5| in the' member 50 isslightly further removed from the rotor axisA Ithan the inner edge ofthe ring dam 22. Accordingly, when the liquid reaches a sufficient depthof the rotor to cause the heavier liquid to be discharged over ring dam22, the liquid entering the conduit 49 and bore 5| will overflow theinner end .of the-bore 5|, and enter the bore 53. The liquid enteringthe bore 53 flows outwardly through tube 54 into bore 51 and into thespace 58 between the inner wall of the housing end portion 36 an'd thepiston 4|. As the pressure in. this space, due tothe head of liquid inconduit 54, increases, this pressure becomes sufficiently great toactuate the piston to cause the valve to be forced against its seatagain. After this ocurs, the valve will be retained against its seat,until it is forced away from that seat invresponse to factorsautomatically resulting from accumulation of sludge in the space 28.During the part of the cycle of operations when liquid is flowing frombore 5| into bore'53 the quantity of liquid passed into bore y51 is morethan sufficientA to offset the amount of leakage from the rotor throughoutlet 60.

After the valves 33 are moved into closed position as discussed above,solids accumulate within the space 28 during the continued feed ofmaterial to the rotor and rotation thereof, and these solids form a wallwithin the space 28 which gradually approaches the extension 38 of thehousing base portion 31. As the accumulation of solids increases, theresistance to flow of liquid into the interior of the housingbase'portion 31 between the inner surface of the accumulated solids andthe base 38 of the skirt'also increases, v

until the flow resistance becomes sufficiently great to offset thedifference in hydrostatic balance between theinner edge of the ring dam22 and the inner end of the bore 5|. When this condition occurs, liquidwill no longer flow into the channel 52 and bore 53 from the bore 5I,and leakage of liquid through the outlet 60 causes diminution of thehead of liquid in the conduit 54, and hence of the pressure against theinner (upper, Fig. 2) end of the piston 4|. The pressure of liquid fromthe sludge space 28 against the opposite side of the piston 4| thencauses the piston to move radially inwardly and draw the valve 33 awayfrom its seat 32, thereby tive through the space between the bed ofsolids and the extension 38, the bore 56, and associated .connectionsgradually increases until liquid is again forced into channel 52 andthrough conduit 54 into the space within the housing end portion 36.After liquid has again passed into conduit 54 to increase the liquidhead sufficiently, the valve will again be closed and the cycle ofoperations may be repeated'indefinitely.

During the operation of the machine as discussed above, the rings 65 and66 perform their sealing function under the influence of centrifu-- galforce, thereby effectively preventing leakage through the space betweenthe relatively moving parts of the fluid pressure motor.

An alternative form of the invention is illustrated in Figure 4. Thisform of the invention is similar to that of Figures 2 and 3 with respectto general assembly and hydraulic connections, but it involves adifferent type of sealing connection. Instead of using a pair of splitmetal rings as sealing members, a single ring 10 of rubber or similarelastically deformable material is mounted between the'stationaryflanges 63 and 64 in the motor of Figure 4. When the rotor is inoperation, centrifugal force acts upon the ring 10 both to force it intight sealing relation to flange 63 and to expand it laterally to forceit into liquid-tight sealing relation with piston 4| and cylinder 59,thereby preventing leakage.

Modifications will be obvious to those skilled in the art and I do nottherefore wish to be limited except by the scope of the followingclaims.

I claim:

1. In a centrifugal separator, the combination comprising a centrifugalrotor provided with a discharge outlet adapted to be alternately openedand closed to control the discharge of an effluent from said rotor, avalve adapted to be moved into discharge-permitting anddischarge-preventing positions, respectively, with respect to saiddischarge outlet, a valve extension connected to said valve andextending inwardly into said centrifugal rotor and a fluid pressuremotor within said rotor secured to saidrotor for rotation therewith andconnected to said valve extension for operating the same, said fluidpressure motor including a member which is stationary with respect tosaid rotor and a member mounted for longitudinal movement relative tosaid stationary member in a direction .having a substantial radialcomponent under the impelling force of fluid pressure, said stationarymember having an abutment for supporting a sealing member, and a sealingmember mounted between said relatively movable and stationary members ofsaid motor l and adjacent said abutment at the inner side thereof,whereby the influence of centrifugal force generated by rotation of therotor forces said sealing member into engagement with said abutment.

2. In a centrifugal separator, the combination comprising a centrifugalrotor provided with a discharge outlet adapted to be alternately openedand closed to control the discharge of an eflluent from said rotor, avalve adapted to be moved into discharge-permitting anddischarge-preventing positions, respectively, with respect to saiddischarge outlet, a valve extension connected to said valve andextendinginwardly into said centrifurotor mounted on a substantially radial axisand secured to said rotor for rotation therewith and connected to saidvalve extension for operating the same, said fluid pressure motorincluding a member which is stationary with respect to said rotor and amember mounted for longitudinal movement relative to said stationarymember in a direction having a substantial radial component under theimpelling force of fluid pressure, said stationary member having anabutment for supporting a sealing member, and a sealing member mountedbetween said relatively movable and stationary members of said motor andadjacent said abutment at the inner side thereof, whereby the infiuenceof centrifugal force generated by rotation of the rotor forces saidsealing member into engagement with said abutment.

3. In a centrifugal separator, the combination comprising a centrifugalrotor provided with a discharge outlet adapted to be alternately openedand closed to control the dischargeof an effluent from said rotor, avalve adapted to be moved into discharge-permitting and discharge-vpreventing positions, respectively, with respect to said dischargeoutlet, a valve extension connected to said valve and extending inwardlyinto said centrifugal rotor and Ia fluid pressure motor within saidrotor secured to said rotor for rotation therewith and connected to saidvalve extension for operating the same, said fluid pressure motorincluding a member which is stationary with respect to said rotor and amember mounted for longitudinal movement relative to said stationarymember in a direction having a substantial radial component under theimpelling force of fluid pressure, said stationary member having anabutment for supporting a sealing member, and an elastically deformablesealing member mounted between said relativelymovable and stationarymembers of said motor and adjacent said abutment at the inner sidethereof, whereby the infiuence of centrifugal force generated byrotation of the rotor forces said sealing member into engagement withsaid abutment.

4. In a centrifugal separator, the combination comprising a centrifugalrotor provided with a discharge outlet adapted to be alternately openedand closed to control the discharge of an effluent from said rotor, avalve adapted to be moved into discharge-permitting anddischarge-preventing positions, respectively, with respect to saiddischarge outlet, a valve extension connected to said valve andextending inwardly into said centrifugal rotor and a fluid pressuremotor within said rotor secured to said rotor for rotation therewith andconnected to said valve extension for operating the same, said fluidpressure motor including a member which is stationary with respect tosaidrotor and a member mounted for longitudinal movement relative tosaid stationary member in a direction having a substantial radialcomponent under the impelling force of fluid pressure, said stationarymember having an abutment for supporting a sealing member, and a rubbersealing member mounted between said relatively movable and stationarymembers of said motor and adjacent said abutment at the inner sidethereof, whereby the influence of centrifugal force generated byrotation of the rotor forces said sealing member into engagement withsaid abutment.

5. In ya centrifugal separator, the combination comprising a centrifugalrotor provided with a discharge outlet adapted to be alternately openedgal rotor and a fiuid pressure motor within said" valve and extendinginwardly into said centrifugal rotor and a fluid pressure motor Withinsaid rotor secured to'said rotor for rotation therewithand connected tosaidv valve extensiontfor operating the same, said ud pressure motorincluding a member which is stationary with respect to said rotor and amember mounted for` longitudinal movement relative to saidstationary'member in a direction having a substantial radial componentunder the impelling force of fluid pressure, said stationary memberhaving an abutment for supporting said sealing ring, and a metal sealingring mounted between said relatively movable and stationary members ofsaid motor and adjacent said abutment at the inner side thereof, wherebythe influence of centrifugal force generated by rotation of the rotorforces said sealing ring into engagement with said abutment.

6. In a centrifugal separator, the combination comprising a centrifugalrotor provided with a discharge outlet adapted to be alternately openedand closed 'to control the discharge df an efuent from said rotor, avalve adapted to be'moved into discharge-permitting anddischarge-preventing positions, respectively, with respect to saiddischarge outlet, a valve extension connected to said valve andextendingV inwardlyinto said centrifugal rotor and a iluid pressuremotor within said rotor secured to said rotor for rotation therewith andconnected to said valve extension for operatlng the same, said uidpressure motor including a member which is stationary with respect' tosaid rotor and a member mounted for longitudinal movement relative tosaid stationary member in a direction having a substantial radialcommovable and stationary members of said mot'or;

and adjacent said abutment at the inner side thereof, whereby theinfluence of centrifugal force generated by rotation of the rotor exertsa sealing force on the outermost ring to seal the space between saidring and said abutment, and a seal-l ing force on said innermost ring toseal the space between said innermost ring and said outermost ring.

7. A centrifugal separator as defined in claim 3, in which said iluidpressure motor is mounted on a substantially radial axis.

8. A centrifugal separator as defined in claim 4, in which said uidpressure motor is mounted on a substantially radial axis.

9. A centrifugal separator as defined in claim 5, in which said fluidpressure motor is mounted onla substantially radial axis.

10. A centrifugal separator as defined in claim 6, in which said fluidpressure motor is mounted on a substantially radial axis.

HAROLD C. FITZSIMMONS.

